They explain that "harare" translates to ha ba robale in Sotho or they don't sleep in English. There is excitement in the air as they fly the flag on the rooftop on a nippy and windy Joburg afternoon.
There is a race against sunset as Thandiswa waits for her tights to be ubered to the venue. They finally arrive and the show gets on the road.
"I can't believe I'm back with these guys. It's been a long friendship and getting back was easy. What we recorded was light-hearted, which is different to my work which takes more from me because it's usually heavier.
"Making music with them is less strenuous because there is always someone to fill up the gap in a song."
While she focuses on the success of Harare, Thandiswa says she still has time to do her solo projects. "I'm polyamorous," she laughs. "I'm writing and working on my own show, Letter to Azania, at the end of November at Lyric Theatre."
I ask if she is bigger than the band. "Nothing can be bigger than Bongo Maffin. You can't be bigger than your family."
She says Harare shows how there's a seamless engagement with other African countries. "It's a reminder that these borders were made by whites to separate us. Ours is a unifying message and a celebration of African cities that don't sleep.
"We are always told about New York, the city that doesn't sleep but our cities don't sleep too... Africans working hard and partying too."
Speedy celebrates his return to the studio with the band, 18 years later. He says there was never any bad blood between them. "I was the nagging one since we started performing together in 2014. There was a gap in the industry and the group was missed. Mafikizolo held it down and it was cool."